Pulp-screen apparatus.



PATBNTED JULY 26, 1904.

Z. LOVEJOY.

PULP SCREEN APPARATUS.

APPLIUATION FILED APR. 23. 1904.

N0 MODEL.

LOQQOQQGD oooeoceao.

UNITED STATES Patented July 26, 1904.

PATENT OFFICE.

ZEBELON LOVEJOY, OF LINCOLN, MAINE, ASSIGNOR OF ONE-HALF TO ELI H.PINKHAM, OF LINCOLN, MAINE.

PULP-SCREEN APPARATUS.

SPECIFICATION forming part of Letters Patent No. 766,150, dated July 26,1904.

Application led April 23, 1904.

T (1,77 'H'mm/ 'l' may concern.'

Be it known that I, ZEBELoN LovEJoY, of Lincoln, in the county ofPenobscot and State of Haine, have invented certain new and usefulImprovements in Pulp-Screen Aqaparatus, of which the following is aspeciiication.

The object of this invention is to simplify and perfect pulp-screens,and especially to reduce the time required in adjusting the old forms ofscreensfthat is, in removing and replacing the perforated plates, as isfrequently necessary in practical use. Under my improvement less thanone-fourth of the time formerly required is consumed in this adjustment,because these simple and efficient fastening's and the screens held bythem are so quickly removed and replaced.

In the drawings, Fig'ure 1 is a top plan of the screen, showing' aseries of perforated plates with interposed locking-bars and endfastenings. Fig'. Q is a longitudinal vertical section on line 2 2 ofFig. 1. Fig. 3 is a transverse vertical section of line 3 3 of Fig. 2.

Each complete screen is furnished with a series of perforated brassplates 5, secured horizontally. The screen-frame is of rectangular formand suitable size, its vertical walls 6 having' a ledge 7 extendingaround their inner face at the base to support the screens proper andtheir fastenings. Flush with the upper face of this ledge and sunken inits opposite side portions are heavy cross-sills 8 and deeply-recessedsills 9, alternating' with and separated from each other a distancenearly equal to the width of a screen-plate.

Each end portion of ledge 7 has made fast to its upper surface ascreen-holding' bar 10, grooved along its inner edge and each of theheavy sills 8 has a like bar 11, grooved in both its edges, thesegrooves receiving the rounded edges of the perforated plates whenintroduced.

Each of the screen-plates has a length equal to the internal width ofthe frame, so that its ends are supported by the ledge 7 and each has arounded edge along' one side to fit into and turn somewhat when insertedSerial No. 204,520. (No model.)

in and removed from the edge groove of the barslO and l1. Eachscreen-plate is also beveled along one edge, these beveled-edge wallsbeing' adjacent to each other and converging downwardly to meet theedges of the longitudinal recess in the cross-sill 9. The fiat bottomsof the plates adjoining' the beveled edges rest on the flat surfaces ofsill 9 cach side of its recess. A transverse wedge-bar 12 is nowintroduced sidewise between these converging walls and extendsdownwardly to lit into and fill the recess of the sill 9, the walls ofsuch recess and of the corresponding lower part of the wedge-bar beingpreferably vertical. The ends of the wedge-bars rest on the ledge 7. ltwill be obvious that when the wedge-bar is introduced between thebeveled edges of the screens they will be pressed apart and held downwith their rounded edges in the grooves of bars and 11, and as the partsare properly proportioned the screen as a whole will present a perfectlyflat internal surface. A screw-eye or other upwardly-extending liftingdevice 13 for the wedge-bar will be provided. The screen may contain asmany pairs of plates with bars thus arranged as may be desired.

The plates and bars forming the screen-bottom are held down lirmly byfastenings quickly detached or replaced. Removable longitudinal bars 14extend along` the side walls, resting on the ends of the plates and barsdescribed. Vertical clamps 15 of peculiar shape are bolted midway oftheir length to the side walls 6, their lower ends resting on the upperedge of bar 14 and extending down partly across its front face, thusholding' said bar down and against the inner wall of the frame 6. Theupper end of each clamp is beveled to fit beneath the beveled undersurface of a projecting rib 16, firmly secured to the inner wall of theframe. IVhen the bolt is tightened, these beveled surfaces tend to forcethe bar 14 down closely upon the screen-plates and cross-bars and theclamp is held from rotation. I prefer to make the lower edge of bar 14somewhat crowning to bring special downward pressure on the wedge-bars12.

For convenience the bolts 17, which secure the clamps, have their headsinside the frame, and their threaded bodies extend outwardly throughclamp and side Wall and are each furnished with a terminal nut 18,having a stem or handle in the plane of its outer face to facilitateturning it sufliciently without a wrench. A washer will be interposedbetween the frame and the nut.

I claim as my inventionl. In pulp-screen apparatus, the frame having asupporting-ledge extending around its inner Wall, cross-sills flush withthe upper surface of such ledge, one of said sills having a deeplongitudinal recess, in combination with perforated screen-platesarranged in pairs, supported marginally on said ledge and sills, andeach having one rounded and one obliquely-beveled longitudinal edge,transverse cross-bars grooved edgewise to receive the edges of saidplates, and a horizontal wedgebar interposed between said beveled edgesand held within such recess by the fastenings for said plates,substantially as set forth.

' '2. In pulp-screen apparatus, the frame having a ledge and cross-sillssupporting a series of perforated horizontal screen-plates, and

transverse bars bearing edgewise on said plates and flush with the uppersurface thereof, in combination with longitudinal bars extending acrossthe ends of said plates and bars, upright clamps bearing endwise on theupper edge of vsuch longitudinal bars and extending down over the facethereof, bolts extending through said clamps and the side of the frame,and

tightening-nuts thereon, substantially as set forth.

3. In pulp-screen apparatus, fixed parts comprising the frame havingaround its inner wall a screen-supporting ledge and near the top of eachside wall a beveled rib, transverse sills between the ends and flushwith the upper surface of said ledge, one of said sills for each pair ofscreen-plates having a deep longitudinal recess, end bars secured to theend portions of the ledge and grooved to receive the rounded edge of ascreen-plate, and an intermediate cross-bar secured to one of said sillsand similarly grooved in both its edges, in combination with removableparts consisting of perforated screen-plates, arranged horizontally, inpairs, supported marginally on said ledge and sills and each having onerounded and one beveled longitudinal edge, a horizontal Wedge-barinterposed between the beveled edges of each pair of plates and enteringthe longitudinal recess in the subjacent sill, lon-` gitudinal barsresting across the ends of said plates and cross-bars, vertical clampsbolted through the frame sides, and bearing at the lower end upon and infront of said longitudinal bars, and beveled at upper end to fit beneathsaid rib, substantially as set forth.

In testimony whereof I have alixed my signature in presence of twowitnesses.

hls ZEBELON 1LOVEJOY- Vitnesses:

ARTEMUs WEATHERBEE, FoREsT L. KNEELAND.

